Minimun function in MS Access

I have 3 fields that have either a 0 or is null or have  a value ~ How can select the lowest value among the 3 fields in MS Access query?  example:
Field 1       Field 2          Field 3       Minimun value would be:
0                                        35.75                35.75
15.01          14.39                    0                 14.39
9.56              7.59                6.59                6.59